In Warcraft 3, map editors were able to import any custom 3d model objects into their maps. I have yet to see a single Starcraft 2 custom games have an imported custom model.

Why is this? Does Galaxy Editor have no such feature? Or is it because of the difficulty?

Edit: Alright, so at least I know that import feature is available, but that still doesn't answer my main question. In WC3, many custom maps were literally flooded with custom models that users could create with ease, which resulted in many, amazingly looking custom maps. After searching through 50 custom games on the top ranked list in NA server, I've found zero map that had imported custom models. I eventually ended up finding ONE map in Korea server that had some imported custom models but the said map only had maybe 2-3 models (I only played it for an hour, so maybe I missed some).

So why are the editors so hesistant in using the custom models in general? Sheer difficulty on creating/importing? Map size limitation? Or restrictions imposed by Blizzard on what type of models you can use (Because the maps have to be kept in the Battle.net Server)? Surely, there has to be some kind of explanation for this.